Difference between SHL and SAL in 80x86

Question

I have learned how to work with 80x86 assembler, so in bit-wise shift operation, I faced a problem with SAL and SHL usage. I means the difference between lines of code as fo

Answer 1

they work the same, since an arithmetic shift is the same as a bitwise shift when it's to the left (increasing). sar, on the other hand, will be different from shr if the sign bit is set.